Flexible ducts are commonly used in residential construction because they provide a low-cost, simple, and efficient duct system for conveying heated and/or cooled air throughout a home. Furthermore, flexible ducts are light-weight and can collapse into a small package which can be easily transported to a construction site. The installation of flexible ducts is far less time-consuming and expensive than using conventional duct work.
While flexible ducts are in wide-spread use, there has yet to be found a simple and reliable method for joining flexible ducts together. Typically, a branch is formed in flexible duct work by using a metal junction box or plenum constructed of sheet metal. The flexible ducts are joined to the plenum using a collar, also made of sheet metal. The plenum is typically constructed on site by the HVAC contractor. A hole is cut in the side of the plenum in which the metal collar is mounted. The flexible duct fits over the end of the metal collar and is secured, usually by duct tape.
In a typical construction project, a substantial portion of the time spent installing duct work is spent constructing plenums for joining flexible ducts together. Therefore, a simpler and easier method for joining duct work is needed which avoids the necessity of constructing plenums for joining duct work together.